Messages in this thread | | | Date | Fri, 26 Jul 2013 18:15:07 +0200 | From | "Arend van Spriel" <> | Subject | Re: [PATCH 9/9] tracing: Remove locking trace_types_lock from tracing_reset_all_online_cpus() |
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On 07/26/2013 03:03 PM, Steven Rostedt wrote: > From: "Steven Rostedt (Red Hat)"<rostedt@goodmis.org> > > Commit a82274151af "tracing: Protect ftrace_trace_arrays list in trace_events.c" > added taking the trace_types_lock mutex in trace_events.c as there were > several locations that needed it for protection. Unfortunately, it also > encapsulated a call to tracing_reset_all_online_cpus() which also takes > the trace_types_lock, causing a deadlock. > > This happens when a module has tracepoints and has been traced. When the > module is removed, the trace events module notifier will grab the > trace_types_lock, do a bunch of clean ups, and also clears the buffer > by calling tracing_reset_all_online_cpus. This doesn't happen often > which explains why it wasn't caught right away. > > Commit a82274151af was marked for stable, which means this must be > sent to stable too. > > Link:http://lkml.kernel.org/r/51EEC646.7070306@broadcom.com > > Reported-by: Arend van *Spril*<arend@broadcom.com>
Nasty dutch names, huh. If we ever meet on a summit you may try to pronounce it :-) Way easier than Finnish.
Regards, Arend
> Tested-by: Arend van *Spriel*<arend@broadcom.com> > Cc: Alexander Z Lam<azl@google.com> > Cc: Vaibhav Nagarnaik<vnagarnaik@google.com> > Cc: David Sharp<dhsharp@google.com> > Cc:stable@vger.kernel.org # 3.10 > Signed-off-by: Steven Rostedt<rostedt@goodmis.org> > --- > kernel/trace/trace.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-)
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